steering head bearings

[philbond07]

Hi all,

Just took me K3n out of wintersleep. Seems upper steering stem bearings make some screeching noise when turning slowly. Are they regreasable, or are they closed & unservicable. Don't even know if they are ball or roller bearings. Tx.

[yorkie_chris]

Yes strip them and grease them.

OEM is caged ball type. You can separate them, outer will remain in frame (press fit), cage and balls will be loose and inner part is sliding fit on steering stem.

[philbond07]

Hey tx Yorkie,

ok great, forgot to ask: what is best grease to use? I think I've got some "Castrol LM grease" around. Will that do?

[yorkie_chris]

Yeah LM is fine. I've got some pyroplex blue here which is ace stuff. But I can't find where to buy a small quantity as it's meant for commercial vehicles.

[maviczap]

This is probably because Mr Suzuki only greased one third of the bearings in your steering head, they like to economise on grease expenditure. Even to ones that were greased, only got a flick :p

[philbond07]

I wonder if it's possible to install a grease nipple for the upper/lower bearings in the steering stem. Did anybody ever manage to do that?

[yorkie_chris]

Not practical unless you wish to fill the entire frame with grease?

No point either, strip them down once a year and they'll be reet.

[philbond07]

Hi again gentlemen,

Found some time to disassemble the steering stem today.

Upper and lower bearings were still well greased. So don't know yet where noise was coming from.
BUT: the lower "stem nut" was stripped when undoing ! No problem undoing "head nut" and upper "stem locknut". Apparently it had been mounted cross-threaded when bike was assembled. So had to apply considerable force to undo it. Very strange. Of course lot of aluminum thread-pieces came off. As the steering stem thread itself is steel I suppose it's still ok (I hope) and the alu was coming of the "stem nut" itself. In the middle of the thread on the stem the steel thread is "interrupted" like by a solid piece that seems to be "welded" on ???. Will try to include a pic later on.
Guess best thing to do is try to rethread steering stem to get rid of solid piece, and get 1 new "stem nut".
Upper & lower bearing inner/outer races seem to be ok.
Bearings themselves: how do you know when they are worn out? There is considerable play of the balls in there cage (like 3-4 mm) but I guess this is normal?

[maviczap]

Hi again gentlemen,

Found some time to disassemble the steering stem today.

Upper and lower bearings were still well greased. So don't know yet where noise was coming from.
BUT: the lower "stem nut" was stripped when undoing ! No problem undoing "head nut" and upper "stem locknut". Apparently it had been mounted cross-threaded when bike was assembled. So had to apply considerable force to undo it. Very strange. Of course lot of aluminum thread-pieces came off. As the steering stem thread itself is steel I suppose it's still ok (I hope) and the alu was coming of the "stem nut" itself. In the middle of the thread on the stem the steel thread is "interrupted" like by a solid piece that seems to be "welded" on ???. Will try to include a pic later on.
Guess best thing to do is try to rethread steering stem to get rid of solid piece, and get 1 new "stem nut".
Upper & lower bearing inner/outer races seem to be ok.
Bearings themselves: how do you know when they are worn out? There is considerable play of the balls in there cage (like 3-4 mm) but I guess this is normal?

Need to see some pics before diaognosing what the problem is

Play in the bearing will go, when you tighten the adjustable bearing thust nut at the top (the one you're supposed to use a C spanner on) Sounds like the alloy has reacted with the steel if there looks like a blob of weld on the steering stem. Shouldn't be like that. OEM top stem nut is steel.

Might need to get your steering stem thread re cut where the blob of weld is?

Pics will help

[philbond07]

ok, the pics

more or less visible: the "weld" on the stem:

http://i265.photobucket.com/albums/ii204/philbond07/DSCN2934.jpg
http://i265.photobucket.com/albums/ii204/philbond07/DSCN2929.jpg
http://i265.photobucket.com/albums/ii204/philbond07/DSCN2928.jpg

[philbond07]

the "welds" are left and right of the washer-groove, nearly at bottom of the groove.

You can see the stem is quite corroded at top :(. Wonder how I'm going to get this off.

[philbond07]

inner race & stem nuts, one of them is crossthreaded:

http://i265.photobucket.com/albums/ii204/philbond07/DSCN2918.jpg

[philbond07]

the bearings, mixed them up but I guess upper & lower are identical?:
http://i265.photobucket.com/albums/ii204/philbond07/DSCN2920.jpg

[philbond07]

upper and lower outer races:
http://i265.photobucket.com/albums/ii204/philbond07/DSCN2921.jpg
http://i265.photobucket.com/albums/ii204/philbond07/DSCN2922.jpg

[Sid Squid]

What welded piece? Are you referring to the vertical slot in the stem?

Looks to me as if the thread has a nick on it - steel hard, aluminium soft - guess which one's ripped? It rahther doubt it would be possible to thread that thin nut all the way it needs to go if it were crossed.

[maviczap]

Looks like a lot of carp on the steering stem thread, get it recut or cleaned with the correct sized thread die.

This has probably ****ed one of the lock nuts thread, rather than cross threaded it

But looking at the bearing face on that stem nut, would indicate that's fubared. Get a new top race and adjusting nut, as well as getting the thread cleaned/repaired

[maviczap]

No, bottom race is different from the top

[philbond07]

What welded piece? Are you referring to the vertical slot in the stem?

Looks to me as if the thread has a nick on it - steel hard, aluminium soft - guess which one's ripped? It rahther doubt it would be possible to thread that thin nut all the way it needs to go if it were crossed.


I call it 2 "welded" dots left and right near bottom of washer groove- hard to see on pics. Of course they are not "welded" there on purpose, but they seem welded. Tried to remove them with sharp screwdriver but didn't work, they seem "welded" there. They also made it hard to remove inner race.

[maviczap]

I call it 2 "welded" dots left and right near bottom of washer groove- hard to see on pics. Of course they are not "welded" there on purpose, but they seem welded. Tried to remove them with sharp screwdriver but didn't work, they seem "welded" there. They also made it hard to remove inner race.

It certainly shouldn't be there, it should be the same as the clean thread, above and below. Maybe waters got in and flowed down that slot and caused some localised corrosion? Or maybe its a manufacturing fault?

[philbond07]

No, bottom race is different from the top

hmmmm can see no difference in 2 bearings :(

[philbond07]

Looks like a lot of carp on the steering stem thread, get it recut or cleaned with the correct sized thread die.

This has probably ****ed one of the lock nuts thread, rather than cross threaded it

But looking at the bearing face on that stem nut, would indicate that's fubared. Get a new top race and adjusting nut, as well as getting the thread cleaned/repaired

Top race looks and feels ok.
About the steel stem thread: Can you see if it's still ok? I don't think a lot of material came off, much harder than the alu nut.

[maviczap]

hmmmm can see no difference in 2 bearings :(

Maybe not on the K3, I was quoting my curvy. Bearings are diiferent dimensions

Check Wemoto for your model, it'll tell you on the spec for the bearing

[philbond07]

What welded piece? Are you referring to the vertical slot in the stem?

Looks to me as if the thread has a nick on it - steel hard, aluminium soft - guess which one's ripped? It rahther doubt it would be possible to thread that thin nut all the way it needs to go if it were crossed.

A nick? You mean sth which shouldn't be there?
I threaded the nut the whole way. Had to use some force.

[maviczap]

A nick? You mean sth which shouldn't be there?
I threaded the nut the whole way. Had to use some force.

If you couldn't do it with your fingers, something isn't right.

[philbond07]

ok the plan is:

- let the stem rethread, local to the "nicks" in order to get rid of them, guess rest of stem thread is ok.
- clean up rest of stem
- get new alu stemnut
- leave upper & lower outer races where they are, both feel smooth.

[maviczap]

ok the plan is:

- let the stem rethread, local to the "nicks" in order to get rid of them, guess rest of stem thread is ok.
- clean up rest of stem
- get new alu stemnut
- leave upper & lower outer races where they are, both feel smooth.

Just make sure all the bearing faces are good, especially on the one at the top & bottom. Clean the bearings up and make sure they are running smoothly.

[philbond07]

Ok Gentlemen, tx to u all for your help. Trying to find new pieces tomorrow.